METHOD OF TREATING RINSING WASTEWATER FROM DEVELOPING APPARATUS FOR PHOTOSENSITIVE LITHOGRAPHIC PRINTING PLATE, METHOD OF DEVELOPMENT, AND DEVELOPING APPARATUS

摘要

A simple method of treating a rinsing wastewater resulting from the development of photosensitive lithographic printing plates. In treating the rinsing wastewater for coagulation, the method enhances coagulation and enables the treated rinsing wastewater to have heightened filterability. The method, which is for treating a rinsing wastewater generating in a developing apparatus for photosensitive lithographic printing plates, comprises (1) adding a cationic polymeric coagulant to the rinsing wastewater, (2) thereafter adding an anionic polymeric coagulant thereto, and (3) then filtering the resultant mixture.